Collapsible Fluid Cartridge With Elastic Membrane

ABSTRACT

A fluid cartridge is disclosed. The fluid cartridge includes a flexible bag body to store a fluid, a nozzle to discharge the fluid and a membrane inside the bag body to assist in the collapse of the bag body during discharging of the fluid.

FIELD OF THE INVENTION

The invention relates to an ink cartridge used in an ink jet printer.

BACKGROUND

High speed production ink jet printers typically implement a fluid cartridge (or ink bag). Such a cartridge employs a flexible casing that is deformable in accordance with consumption of ink therein. However, fluid cartridges tend not to empty fully when external air pressure is applied. This is mainly due to wrinkles forming on the creases of the side walls that do not flatten out as the bag empties, thus trapping fluid when emptying.

Accordingly, a mechanism to enable full emptying of a fluid cartridge is desired.

SUMMARY

In one embodiment, a fluid cartridge is disclosed. The fluid cartridge includes a flexible bag body to store a fluid, a nozzle to discharge the fluid and a membrane inside the bag body to assist in the collapse of the bag body during discharging of the fluid.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the present invention can be obtained from the following detailed description in conjunction with the following drawings, in which:

FIG. 1 illustrates a top view of one embodiment of a fluid cartridge;

FIG. 2 illustrates a rear view of one embodiment of a fluid cartridge;

FIGS. 3A and 3B illustrate embodiments of a permeable membrane; and

FIGS. 4A-4C further illustrate rear view embodiments of a fluid cartridge.

DETAILED DESCRIPTION

A mechanism to enable full emptying of a fluid cartridge is described. In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without some of these specific details. In other instances, well-known structures and devices are shown in block diagram form to avoid obscuring the underlying principles of the present invention.

Reference in the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.

FIG. 1 illustrates a top view of one embodiment of a fluid cartridge 100. In one embodiment, fluid cartridge 100 includes a bag body 102 formed by flexible sheet members and configured in a manner, for example, that flexible sheet members such as gas-barrier laminate films each formed by depositing aluminum on a polyethylene film are overlapped, and heat welding seal is performed along the outer periphery of the overlapped sheet members to form a welded portion.

Fluid (e.g., ink used for printing) is stored within cartridge 100 and is discharged via a nozzle 105 at one end edge of body 102. In one embodiment, nozzle 105 is formed by a hard material, such as composite resin. Body 102 includes sidewalls 107, sidewall creases 110 and a membrane 120 attached to sidewall creases 110. In one embodiment, membrane 120 is an elastic permeable membrane that is implemented to pull in the sidewalls 107 such that the side walls 107 fold and collapse along respective creases 110 to aid in the collapse of cartridge 100. In other embodiments, membrane 120 may be comprised of any elastic material that does not interact with the ink within cartridge 100.

FIG. 2 illustrates a rear view of one embodiment of fluid cartridge 100 in which membrane 120 is attached to creases 110. As shown in FIG. 2, sidewalls 107 are folded, and the cartridge 100 material is fused with membrane 120 inserted in between. Accordingly, membrane 120 is comprised of material that is able to withstand fusing temperatures.

FIG. 3A illustrates one embodiment of a membrane 120 used to pull in side walls 107. In this embodiment, vertical bands 310 are elastic, while horizontal bands 320 are not. In such an embodiment, horizontal bands 320 are implemented to hold vertical bands 310 in place, with the gap between bands 310 enabling the cartridge 100 material to come together to provide a better fuse at crease 110. In a further embodiment, vertical bands 310 are fused perpendicular to the crease 110 line to permit crease 110 to fold properly. In still a further embodiment, the angle (σ) between bands 310 and 320 is 90°. However in other embodiment, σ may vary between 0° and 90°.

FIG. 3B illustrates another embodiment of a membrane 120 having circular cutouts 330. In this embodiment, cutouts 330 have a horizontal orientation to enable membrane 120 to stretch. In one embodiment, membrane 120 exerts an elastic force in a perpendicular direction to that of the crease 110 to aid in collapsing of the bag. FIGS. 4A-4C illustrate embodiments of a rear view of fluid cartridge 100 during various stages of ink fill.

As shown in FIGS. 4A-4C elastic membrane 120 pull together sidewalls 107 at crease 110, aiding in the collapse of fluid cartridge 100. For instance, when bag body 102 is at the fullest position, the membrane is exerting a maximum elastic force on the side wall creases 110. FIG. 4A shows cartridge 100 at the fullest position, with the elastic force being measured at X. As ink is drained from bag body 102, membrane 120 exerts a force in the collapsing direction to assist in the draining.

FIG. 4B illustrates a further embodiment of cartridge 100 after fluid has been discharged. As shown in FIG. 4B, the dimensions of bag body 102 are unchanged. However, the elastic force of membrane 120 is measured at Y, where X>Y. has moved in a perpendicular direction marked by a location at a distance Y. FIG. 4C illustrates yet another embodiment of cartridge 100 after fluid has been completely drained. In this embodiment, bag body 102 is at its flattest position with the dimensions remaining unchanged. However, membrane 120 is exerting a minimal elastic force measured at Z, where X>Y>Z.

Whereas many alterations and modifications of the present invention will no doubt become apparent to a person of ordinary skill in the art after having read the foregoing description, it is to be understood that any particular embodiment shown and described by way of illustration is in no way intended to be considered limiting. Therefore, references to details of various embodiments are not intended to limit the scope of the claims, which in themselves recite only those features regarded as essential to the invention. 

What is claimed is:
 1. A fluid cartridge comprising: a flexible bag body to store a fluid; a nozzle to discharge the fluid; and an elastic membrane inside the bag body to assist in the collapse of the bag body during discharging of the fluid.
 2. The fluid cartridge of claim 1 wherein the bag body comprises sidewalls having creases.
 3. The fluid cartridge of claim 2 wherein the membrane assists in the collapse of the bag by pulling in the sidewall creases.
 4. The fluid cartridge of claim 3 wherein the membrane exerts an elastic force in a perpendicular direction to the sidewall creases to aid in collapsing of the bag.
 5. The fluid cartridge of claim 4 wherein the membrane exerts a maximum elastic force when the bag body is full.
 6. The fluid cartridge of claim 5 wherein the membrane exerts a minimum elastic force when the bag body is empty.
 7. The fluid cartridge of claim 2 wherein the membrane is fused into the sidewall creases.
 8. The fluid cartridge of claim 2 wherein the membrane comprises: a plurality of vertical bands; and a plurality of horizontal bands.
 9. The fluid cartridge of claim 8 wherein the horizontal bands hold the vertical bands in place.
 10. The fluid cartridge of claim 8 wherein an angle between horizontal bands and the vertical bands is 90 degrees.
 11. The fluid cartridge of claim 8 wherein an angle between horizontal bands and the vertical bands is less than 90 degrees.
 12. The fluid cartridge of claim 8 wherein the vertical bands are fused perpendicular to a line of the sidewall creases to permit folding.
 13. The fluid cartridge of claim 8 wherein the vertical bands are elastic.
 14. The fluid cartridge of claim 2 wherein the membrane comprises circular cutouts.
 15. The fluid cartridge of claim 12 wherein the circular cutouts have a horizontal orientation.
 16. The fluid cartridge of claim 2 wherein the membrane is comprised of an elastic permeable material. 